System and apparatus for facsimile telegraphy



Sept. 16, 1941. R. J. WISE HAL 2,255,868

SYSTEM AND APPARATUS FOR FACSIMILE TELEGEAPHY Original Filed Nov. 15, 1956 ll SheetS-Shet l lNVENTORS R.J.W G.H.Rl NGS .Sept. 16, 1941. R. J. WISE ET AL SYSTEM AND APPARATUS FOR FACSIMILE TELEGEAPHY Original Filed Nov. 13, 1956 11 Sheets-Sheet 2 FIG. 2

Sept. 16, 1941. R. J. WISE ET AL SYSTEM AND APPARATUS FOR FACSIMILE] TELEGRAPH! ll Sheets-Sheec 5 Original Filed Nov. 13, 1936 FIG. 3

INVENTORS R. J. WISE Sept. 16, 1941.

R. J. WISE ET AL ori inal Fil ed Nov. 13, 1936 SYSTEM AND APPARATUS FOR FACSIMILE TELEGEAPHY ll Sheets-Sheet 4 jau Sept. 16, 1941.

FIG. 6

R. J. WISE ET AL 2,255,868

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Original Filed Nov. 13, 1956 11 Sheets-Sheet 5 INVENTORS F. E. d'HU MY wg, 6W

ATT RNEY Sept. 16, 1941. R. J. WISE ET AL ,8

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Original Filed Nov. 13, 1936 11 Sheets-Sheet 5 INVENTQRS R.J.WISE G.H.RIDINGS. F.L.O'BBVIEN \F. E dHUMY 5 Mai/37M ATT RNEY Sept. 16, 1941. R. J. WISE ET AL 23 SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Original Filed Nov. 15, 1956 ll Sheets-Sheet 7 PEG; @2

v I I 573 l WI INVENTORS R.J. WISE G.H.RID| NGS BY F.L.O'BR|EN d'HUMY M6. ATmRNEY Sept. 16, 1941. R. J. WISE ET AL SYSTEM AND APPARATUS FOR FAGSIMILE TELEGEAPHY Original Filed Nov. 13, 1956 ll Sheets-Sheet 8 INVENTORS *R.J. w|s

G.H. mamas BY F. L.O'BRIEN y. E.d'HUMY ATTORNEY Sept. 16, 1941. I R. J. WISE ET AL 2,255,868

SYSTEM AND APPARATUS FOR FACSIMILE TELEGEAPHY Originai Filed Nov. 15, 1956 ll Sheets-Sheet 9 INVENTORS R.JWISE' G.H.R|D|NGS BY EYN ATT FRNEY R. J. WISE ET AL Sept. 16, 1941.

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPH! ll Sheets-Sheet 10 Original Filed Nov. 15, 1936 FIG. IH

CONSTANT LENGTH\l Sept. 16; 1941. R. 1. WISE ET AL 3 SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Original Filed Nov. 15, 1955 11 Sheets-Sheei 11 IHMU I.

F. E. dHUMY FIG; l3

Patented Sept. 16, :1941

,SYSTEM AND APPARATUS FOR FACSIMILE TELEGBAPHY Raleigh J. Wile, Dunellen, Garvice H. Ridings, Summit, and Frederic L. OBrien, Lyndhurst, N. 1., and Fernand E. dHumy, Scarsdale, N. Y., minors to The Western Union Telegraph Company, New York, N. Y a corporation or New York Application November 1 3, 1936, Serial No. 110,760

Renewed June 22, 1940 57Claims. (01.

The present invention relates to telegraphy and more particularly to an automatic system and apparatus for transmitting and receiving messages, pictures and other subject matter in facsimile.

The primaryobject of the present invention is to provide a facsimile telegraph system including one or more interconnected sending and receiving stations with means at each station to cause automatic transmission and reception of a message or a plurality of successive messages.

Another object of the present invention s to provide novel automatic apparatus capaoe of serving either as a facsimile transmitter or receiver.

In accordance with the present invention, pictures, messages or other subject matter are transmitted from or received upon a subject matter sheet carried by interchangeable copyholders which are automatically placed in operative position in the combined transmitter recorder and removed therefrom. In the preferred form of the invention, picture or message sheets are carried by interchangeable cylinders. Accordingly, still another important object is toprovide a facsimile transmitter and receiver having autoatic means for supplying messages or pictures succession for transmission, or message blank-s in succession for reception.

A further object is to provide a novel remote 03 system for effecting control of apparatus ta'nt point.

A still further object of the present invention is to provide a facsimile telegraph system embodying novel means for phase control of received copy. A still further object of the present inventio resides in the provision of novel means for re taining a flexible sheet on a platen.

A still further object of the present invention is to provide novel means for producing an end of transmission signal. I

The foregoing and other objects of the invention will appear from the following description of an illustrative embodiment of the invention and modifications thereof.

In the drawings:

Fig. 1 is a perspective view of a facsimile transmitter or receiver embodying the invention in one of its preferred forms;

Fig. 2 is an enlarged fragmentary elevational view taken partly in section approximately on line 22 of Fig. 1; 1

Fig. 3 illustrates diagrammatically the electable or other convenient support.

trical features of a control system in accordance with the invention;

Fig. 4 is a diagrammatic showing of the electrical features of a modified control system;

Fig. 5 is a fragmentary view in front elevation illustrating a modified construction of'parts shown in Fig. 1;

Fig. 6 is a view in front elevation of a facsimile transmitter or receiver embodying the invention in a modified form, certain of the parts being broken away and others shown in cross section on line 6-6 of Fig. 7; i

Fig. 7 is a view in sectional elevation of the apparatus of Fig. 6, the section being taken on line i-i and partly on line IV-l thereof;

Fig. 8 is a diagrammatic showing of the electrical features of a modified control system suitable for use with the apparatus of Figs. 6 and 7;

Fig. 9 is a view in front elevation of a facsimile transmitter or receiver embodying the invention in another modified form;

Fig. 10 is a sectional elevation taken on line lt-ld of Fig. 9;

Fig. 11 is a diagrammatic showing of the electrical features of a modified control system suit- .able for use with the apparatusof Fig. 9;

Fig. 12 is a fragmentary view showing a sheet holding device provided with an end of message indicator or control in accordance with the in vention;

Figs. 13 and "M are a top plan and a sectional elevation, respectively, of a modified receiver embodying the invention; and

Fig. 15 is a schematic diagram of the electrical circuits of the receiver of Figs. 13 and 14.

Certain features of the transmitter-receiver disclosed and claimed in the application of Raleigh J. Wise. Se'r. No. 84,935, entitled System and apparatus for facsimile telegraphy and filed June 12, 1936, now Patent No. 2,158,391, are shown in the present application with detail parts omitted for the sake of clearness in combination with automatic copy changing means thereby providing a novel automatic transmitter-receiver.

Referring to the drawings. and for the present to Figs. 1 to 3 thereof, i0 indicates a base-which .forms the principal support for the operating parts and driving mechanism of the apparatus and which is adapted to rest upon an apparatus The base is provided with guide rails l2 and I4 serving to support slidably the longitudinally movable scanning assembly I5 which comprises the optical pickup system, indicated at I6, for sending messages and if desired the independent stylus ll (Fig. 2) which may be employed either for transmitting or receiving. The scanning assembly I3 is mounted upon a suitable base member l9 (Fig. 2) which is provided with a suitable number of bearing guide blocks 20 grooved or otherwise formed appropriately to slidably engage the guides l2 and I4. Movement in one direction is imparted to the scanning assembly by means of a rotatably mounted threaded rod 23 which is journalled in suitable bearings (not shown) projecting from the base 10. An apertured guid member l8 mounted on'the base IQ of the scanning assembly has secured thereto a member 24 which The plunger 25 of the carries a solenoid 2|. solenoid 2I is connected by a link 26 to an elongated member 21 provided with an arcuate threaded recess adapted for engagement with the threads on the rod 23. A tensioned cable, similar .left when the solenoid plunger 25 raises the halfsynchronous or speed regulated motor, through a nut 21. The cable may be tensioned by any suitable weight or spring device, for example by a spring reel, such as is used to exert tension on a typewriter carriage.

The subject matter to be scanned, which may be messages or pictures either for purposes of transmission or reception, is carried upon readily interchangeable copyholders preferably in the form of cylinders 28, as shown in the copending patent above referred to and illustrated in Figs. 1

speed reduced drive 43 of suitable character, and 4 a friction clutch 48. A disc 41 mounted on the driven shaft 43 has a notch 48 in its periphery adapted to be engaged by the armature of a magnet 43 to retain the shaft at rest when the magnet is deenergized. A commutator 50 having a single insulated section is also secured to the shaft 43. The threaded shaft 23 may conveniently be driven from a speed reducing drive (not shown) at the opposite end of the motor 44. The gear ratios of the gearing just described and the pitch of the threads of rod 23 are selected so that the rate of longitudinal travelof the scanning'assembly I5 and the peripheral speed of rotation of the cylinder-28 cooperate to produce the desired helical scanning of the subject matter on the cylinder. Excellent results are secured in practice for message transmission by selecting these relative speeds so that as the cylinder 28 rotates once, the scanning assembly will move longitudinally a distance of a hundredth of an inch. 1

To provide for a positive but automatically engageable driving connection between the driven shaft 43 and the cylinder 28, a resilient dog clutch is provided which comprises a radially extending pin 5|, which projects from the shaft 29 of each cylinder 28 adapted foruse in the device, and a driving member 52 which is pivoted to the shaft 43. The member 52 is urged against a stop 53 secured to the shaft 43 by means of a tensioned spring 54, best shown in Fig. 9, th said spring for the sake of compactness of design partly encircling the shaft 43.

The previously mentioned independent-stylus ll, which may be used for recording, is either pivotally or resiliently mounted and is connected by in a concentric position as described in the patfixed to any stationary part, for example, to the bracket 35 as illustrated in the drawings. Moveiilent of ,the rod 33 under the influence of the spring is normally limited by engagement of the conical end of the rod with the hollow end of the shaft 23 of a cylinder 28, but when there are no cylinders in the apparatus, a pin 40 protruding from the shaft 33 engages with the tongue 4| of a normally open switch 38 to close the same. The purpose of the switch will be pointed out in a later description of the control circuits .shown on Fig. 3. A conical point 42 which is formed at the end of a 'drivenshaft 43 is compiementary to the conical point 32, and it is to be a link 56 (Fig. 2) to the plunger 25 of the previously mentioned solenoid 2| whereby it is raised from its operative position along with the halfnut 21 upon energization of the solenoid in a manner to be described. In the arrangement specifically shown by Fig. 2, the stylus is pivoted at 58 to a fixed part of the assembly l5 and is held in contact with the cylinder by a spring 58',

whereas in the modified construction shown in Fig. 5 of the drawings, the stylus indicated by the numeral I1 is resilient and forms the armature of a magnet 59 which serves to withdraw it from contact with the cylinder.

The parts thus far described, with the exceptionof theclutch 46, the stop disc 41 and the solenoid for raising the half-nut 21, and the stylus H, are substantially like those disclosed in the copending Wise et al. Patent No. 2,158,391, I previously referred to. The automatic feeding and removal in succession of a plurality of cylinders 28 is an important part of the present invention and the apparatus in combination with the parts just described for carrying it out will now be described in detail. It will be understood that the description which is to follow ofthe details ratus is applicable to both transmission and reception.

noted that as the rod 33 is permitted to be moved toward the left, the conical points 32 and 42 will enter the ends of the shaft 29 of a cylinder 28 to raise and position it accurately in alignment with the shaft 43 and the rod 33 in the manner pointed out in the patent previously referred to.

The cylinder driving shaft 43 is driven from the motor 44, which is preferably some form of I As shown in Figs. 1 and 2, a rack or magazine indicated generally on Fig. 2 by numeral BI, is provided to hold the cylinders 28 in readiness to be fed, one at a time, into the scanning device. The magazine 6| comprises two similar rail members 63, only one of which appears in Figs. 1 and 2, carried by corresponding uprights 65 and 66, the latter being secured by suitable fastening means 61 to the base Ill. The rail members 63 I are each provided with a sloping edge 88 upon shown in Fig. 1, and a plurality of copyholders in readiness for scanning may be supported upon an auxiliary rack or magazine composed of a pair of suitably supported spaced rails 69 (Fig. 2). A pair of resilient upright members secured to the rail members 63 cooperate with the 'downturned ends ll of the rails 69 to guide the copyholders 28 onto the sloping edges 68. One of a pair of similar stops I3 is pivotally secured on each of the rail members 63 at I4 and is biased outwardly beyond the edge 60 by a spring I5.

The copyholders, fed one at a time from the magazine 6|, are received in a cradle composed of a pair of tiltable supports 11 and 18 which are secured at their ends to a shaft'lii, the latter being journalled at one end in a bearing support 8! secured to the base Ill. The tiltable supports are notched as indicated at E6, to accommodate the spindles 29 of the copyholders which are fed to the operating position. The forward edges 80 of the notches 16 are in alignment with the edges 68 of the rail'members 63 when the cradle is in its upright position. The other end of the shaft is is journalled in and projects beyond the support 35 for a purpose tobe described.

A pair of similar uprights 8d are each provided with vertically spaced fingers 85 which project outwardly to cooperate with fingers 86 on the uprights 65 and $6. A copyholder, released. from the centers 32 and #32 following completion of a scanning operation and resting temporarily on the supports ii and it, is discharged onto the upper fingers 35 and rolls from these to the fingers 86 and then to the lower fingers 85, when the supports are tilted by'rocking the shaft i9. Additional fingers 85 and 86, may be added if 'desired, or a suitable receptacle or conveyor may be associated with the base to accumulate or remove copyholders. The extended end 8? of each of the supports Ti and i8 is adapted for engagement with its corresponding detent 13, as will be hereinafter described, when the supports are tilted by rocking the shaft 79, so as to release a copyholder resting on the edges 58. The released copyholder thereupon rolls down until it is in contact with the ends 87 of the tilted supports. When the upports 77 and 18 return to the upright position illustrated in Fig. 2 of the drawings, the fresh copyholder, which passed the stops '78 when they were depressed by the ends 87, is free to roll down and seat itself within the aligned notches it.

Rocking movements are imparted to the shaft '19 means of an arm 88 (Fig. 2), which is secured to the end of the shaft i9 projecting through the upright 35. The outer end of the arm 88 is provided with a cam follower 89. A spring 90 suitably secured to the base H3 and to a member 9i on the support 18 serves to bias the supports to an upright position.

A cam shaft 92' rotatably supported in bearing brackets I06 is driven from a motor 93 through gears 94 and 95 and in operation of the apparatus this shaft operates the several parts of the automatic copy changing means. The shaft 92 has a cam 96 secured thereon which engages the cam follower 89, described above, for rocking the shaft 19. .A second cam 91 cooperates with a cam follower 98 secured to one arm 99 of a bell crank pivoted in a U-shaped bracket I00 carried by the upright 34. The second arm llll of the bell crank is bifurcated, as shown, to engage a pin I02 extending through the spindle 33. A third cam I03 fixed to the shaft 9| is provided with a cam lobe I04 which opens the switch we once in each revolution of the shaft 92. The function of the switch J 05 will be later described in connection, with rig. 3 of the drawings.

The peripheral configuration of each cam just described is designed so that the notched uprights 11 and 18, the spindle 33 and the switch I 05 are'operated in proper sequence and for a period of time necessary to accomplish their several functions. To prevent excess overtravel of the cam shaft upon completion of a cycle of operation of the automatic apparatus Just described, the motor armature shaft is provided with a brake drum Hill which is engaged under the influence of a tension spring 509 by brake shoes carried on the pivoted arms Hit. The brake shoes are released by the spreading of arms I08 under the influence of a magnet Ht whichis energized at an appropriate time, in a manner to be described in connection with the electrical features of the apparatus illustrated in Fig. 3.

In operation of the mechanical parts of the apparatus thus far described, the copyholders 28 are prepared in advance and placed upon the rails es in any desired sequence. The foremost copyholder occupies the position illustrated in Fig. 2 with its spindle 29 in engagement with both of the detent members it. It will be assumed for motor 93 is started, which causes the shaft 92 tocommence rotation in a clockwise direction as.

viewed in Fig. 2. It will be noted that the cam 97 withdraws the spindle 33 toward the rightalmost immediately by reason of the shape of its peripheral outline. drawn toward the right, the copyholder 28 between the centers 32 and 32' is released and drops into the notches it in the cradle '52 and at that time the cam 96 causes the shaft is to rock, tilting the members Ti and it toward the left as indicated by the dot and dash outline. The copyholder, released from the centers 32 and 42, as just explained, rolls along the edges of the notches E6 and is discharged onto the fingers carried by the supports d ll. At the same time the upper ends 8? of the supports fl and it press the 96 allows the shaft 79 to rotateunder the infiuence of the spring which restores members Ti and 1a to their upright position. As the cradle '12 starts to rise to its upright position, the

copyholder 28 which is resting against the top When the spindle 33 is with-' to be raised intoscanning position. Just before the shaft 8i completes its cycle oi rotation, the

switch I05, which controls the stopping of the will be reclosed in readiness for the next cycle of operation.

The cyclical functioning of the mechanical ,parts just described may be controlled in any suitable manner without departing from the. spirit of the invention. In Fig. 3 is shown a preferred control arrangement of this invention governed in accordance with the longitudinal portion of a copyholder occupied by any subject matter of the length of a verbal message. The control-system of Fig. 3 is illustrated in connection with a ahead of the scanning device while still maintaining a flrm grip on the message sheet.

If the sheet I54 has a written message on its face, it is preferably wrapped around the copyholder 28 so that the lines of written or printed matter will encircle the copyholder. In this way a short message will extend axially along the copyholder for a shorter distance than will. a long message. An important feature of the invention relates to the provision of means to ensure a change of copyholders 26 when the end of a message is reached thus effecting an important sav- 'ing of line time. One way of controlling the means for changing the copyholders through the agency of the annular springs I56 and I51 and a switch I60, is disclosedin Fig. 3 of the drawings.

combined transmitting and receiving station embodying the invention. For the sake of convenience of illustration, certain of -the mechanical parts, appearing in Figs. 1 and 2, are reproduced in diagrammatic form, and also some of the parts which perform different functions, depending on whether the apparatus is used as a transmitter or receiver, are shown twice, once in a group with the transmitter parts and again in a group with the receiver parts. For example, the stylus I1 and the copyholder 28 are shown in the lower right hand section of Fig. 3 andare again reproduced in the upper right hand section with the receiver parts. The parts which cooperate especially to send copy appear generally in the lower left hand corner of Fig. 3 while the recorder parts are grouped generally in the upper right hand 7 part of the figure.

The transmitterparts comprise a motor 44 v which, as stated, drives the shaft 43 through a slip clutch 46 of any suitable type to be found in the prior art. The clutchv 46 is necessary only when the sender and the receiver at the remote station are driven by motors which do not run at precisely the same speed. when both motors do operate at the same speed, the clutch may be dispensed with in accordance with the invention. The shaft 43 is released for rotation upon energization of the magnet 49 (repeated in the wiring diagram) through the armature I22 and front contact of a'relay I23. When the apparatus is used for transmitting, the magnet 48 is not needed and its armature may be retained out of engagement with the disc 41 by means of a manual latch I24.

The copyholder 28 between the' centers 32 and 42 is shown as holding a sheet I54 bearing a picture or message ofany desired length. If the ,-transmitter-recorder is being used as a receiver,

the sheet I54 will be anydesired type of recording blank.

vantages are possessed by the elastic retaining bands of this invention, as will be apparent tothose skilled in the art, and in addition, new and special results accrue from their use with the automatic apparatus disclosed. One important advantage is that several bands may be placed at difierent points along the copyholder because as The switch I60 is suitably mounted on the base I 9, preferably adjacent the optical pickup I6, and comprises a resilient tongue or arm I6I which has a projection I62 to engage the band I56, the latter having coils of such diameter that it will roll easily when it is pushed along as the switch I60 moves to the right with the base I8 during a scanning operation. The band I51 is made up of heavier material having smaller convolutions than band I56 and therefore it will not roll as readily as the latter. When the band I51 is located along the copyholder 26 at or Just beyond the end of a message, the band I56, as it is propelled by the switch arm I6I, will be checked in its free movement as it contacts with the band I51, causing the switch arm I6I to be pressed to the right with. respect to the base I8 and into contact with the switch arm I62. This affords a convenient way of retaining the copy in position as scanning proceeds and provides a simple and effective means for controlling the removal of the copyholder and insertion of a fresh copyholder by the mechanism previously described.

Upon closing of the switch I60 a circuit is completed along the wire I63 to one coil I65 of a" relay I66. The circuit including the relay coil and the switch I60 is. completed through a condenser I61 of relatively large capacity which is shunted by a high resistance I61. A suitable source of current I68 serves to supply power for the electrical apparatus disclosed in Fig. 3 of the drawings and is connected to one terminal of the condenser I61 and resistance I 61'. A switch I10 is provided so that the coil I65 ofthe relay I66 may be connected at the point marked T to the conductor I63 whenthe apparatus is used for I transmission or at the point marked R, to the back contact I12 of a relay I13 when the appaenergized fromthe current source I 68 through conductor I16, switch I05, front contact I 11 and the relay tongue I18 to ground. The switch I05 previously described in connection with Fig. 1 of "the drawings, is mechanically operated by the cam I03 after the copyholder changing mechanism completes its cycle, so as to open the locking circuit established over the conductor I16.

A relay I80 is energized through the tongue I18 and contact I11 of the relay I66. The armature tongue I82 of the relay I80 completes a circuit from ground through the cylinder changing motor 93 to the current source I68 and at the same time energizes a relay I83 which applies ground scanning proceeds, the bands will roll freely through its contact tongue I84 to the conductor The desired results are'best obtained I", to energize the operatin coil of a relay I81 and the coil I88 of a relay I00. The relay I'I controls eneigization of the half-nut lifting sole-' noid 2| through its grounded front contact I02,

hausted. A bell m and a lamp I88 in circuit with the switch 80 serve as warning signals Indicating that the machine is idle.

The double pole switch I89, which is disclosed for the purposeof describing the operation of the mechanism as a transmitter, completes the circuit of the operating coilJ 88 of the relay I90 from the conductor I86 to the source of potential I68. A holding coil 200 of the relay I90 locks the relay through its left hand tongue 2.0I by way of a conductor 202 and an interrupter or rotating commutator switch 50. The commutator switch in the form shown comprises a metallic disc and the brushes 206 ride on the periphery thereof. An insulated section 208'in the periphery serves to interrupt the circuit established through the conductor 202 at a given point in each revolution of the shaft I I6. It should be noted that the relay I'90 is always kept energized by its operating coil I88 as long as the relay I86 remains locked. The function of relay I90 is to connect a carrier shown inthe R. J. Wise Patent No. 2,l58,891, re-

, 28, 1836, is preferably employed in the manner ferred'to above, in which case the device M6 is connected to the recording stylus II.

A branch circuit 2" leads to a six thousan cycle filter or tuner 220 which feeds into an amplifierand detector 22I. The output of the detector. 2 is connected to its supply source 222 through a relay 224. The slow release relay I13, previously mentioned, is controlled through the tongue and the back contact 228 ofthe relay 224.

A push button or other switch 22], suitable for manual operation, is connected toone terminal of the operating coil I66 of the relay I68. One terminal of the switch 221 is grounded and when it is closed momentarily by hand, the automatic apparatuschanges a copyholder, as hereinafter described.

The operation of the apparatus of Fig. 3 will now be described with particular reference to the electrical features thereof, the operation of the source 201 with the transmission channel L when source 201 to the line.

The carrier source 201 may generate an alternating current of any convenient frequency suited for transmission over the communication circuit L. Because of the novel arrangement of the electrical features of the receiving apparatus, the

fundamental frequency of the source 201 may be close to the carrier frequency produced or modulated by the pickup device I6. This has the advantage of economizing on band width in the channel L necessary for transmission of pictures and the control tone. In use it has been found satisfactory to employ a six thousand cycle source 201, for example, when the subject matter carrier frequency is five thousand cycles. For convenience in the description which is to follow 01 the electrical features of the automatic transmitter-receiver used as a receiver, the subject matter frequency will be spoken of as five thousand cycles and the receiver operating frequency from the source 201 as six thousand cycles, but it will be understood that other frequencies may be selected without departing from the spirit of the invention.

To adapt the automatic transmitter-receiver for operation as a receiver, several simple pieces of apparatus now to be described are added. The output of the amplifier RA of a suitable type is fed by conductors 2I6 to an amplifier or detector device 2| 6 of a kind best suited for the method of recording which is employed. The dry method of recording disclosed in'the copending application of R. J. Wise et al., Ser. No. 23,928, filed May mechanical parts having already been discussed. Assuming first for purposes of illustration that a message onthe sheet I54 is being transmitted. the signals are generated in the pickup device I8 and are given the preliminary amplificationtherein following which they are amplified by the transmitting amplifier TA and passed onto the line L by way of the contact 2 and the switch tongue 209 of the relay I90, the switch 200 being set at its transmitting position T. After the scanning light beam, or stylus if it is used, of the transmitting device I6 reaches the end of the message, the elastic band I56 presses against the band I51 which was placed Just beyond the end of the message and the added mechanical load imposed on the spring I8! causes it to close the contacts I62. Upon closing, these contacts complete a circuit through the operating winding of the relay I66,'the switch I10 being in its transrnitting position T. This'relay operates and is locked through its winding I76 and contact ill.

The locking circuit thus established includes the Y normally closed contacts I08. In addition to locking itself, the relay I66 energizes the relay I80 which in turn applies battery to the copy- I holder changing motor 98 and also energizes the relay I83 causing the half-nut release solenoid ill to operate through the action of the relay I81. The relay I83 also energizes the operating winding I88 of the relay I90. The half-nut having been disengaged from the carriage feed screw as previously described, the carriage I9 returns under the influence of its retractile spring while the cylinder 28 is being. changed hy the mechanism driven by the motor 93, as previously described. The relay I90 locks itself through the tongue 20I by way of the conductor 202 and the brushes 205 which rest on the conducting drum 208.- This interrupting circuit, however, is interrupted once for each revolution of the shaft 6. It should be noted that the relay I90 is also kept energized by its'operating coil I88 as long as relay I66.remains locked.

The relay I90 is the tone switching relay which When the drum changing mechanismh'as completed its cycle of operation, at which time the shaft 92 has made one revolution, as was fully explainedin connection with Figs. ,1 and 2 of the drawings, the contacts of the normally closed the -ceiving positions.

I03. This opening of the contacts releases the tongueil18 of the relay I66 thereby deenergizing Q switch I05 are opened momentarily by the camsulated segment 206 of the otherwise solid metalconductor. I86 are deenergized, the relay I90 is also deenergized and restores the transmitting device I6 to the line L at contact 2.

It will be noted that the commencement of the six thousand cycle tone to the line is controlled by the end of message feature and that this tone is kept on the line while the mechanism is going through the cycle of reloading'the machine with a fresh copyholder 28, and the tone is taken ofl the line at a definite moment with respect to a has been disconnected by throwing the switch I88 to the receiving position. The cycle of operation explained In detail heretofore is carried out, resulting in the positioning of a fresh copyholder 28 in operative scanning position.

Just as the drum changing mechanism completes its cycle of operation'it opens normally closed contacts I05, as previously described in connection with the operation of the machine as a transmitter, and this deenergizes the holding winding of the relay I66, releasing its contact tongue I18. It is to be noted that there is no appreciable current through the winding I65 even though the six thousand cycle tone is still coming in and the contacts of the relay I13 are closing a circuit through the winding I65,'in series with the high resistance I61. Initially this circuit was operable because of the high charging current through the condenser I61. The winding I65 will be again'efiective after the relay I13 has opened this circuit for about two seconds and allowed the condenser I61 to lose its charge given point on the revolving message drum. The

sheet I54 is placed on the cylinder with the lap of the sheetin a definite position relative to the pin 5i and the insulated segment 206 is so posi-.

respect to the passage of the lap of the sheet I54.

beneath the pickup device [6.

The operation of the apparatus of Fig. 3 as a receiver will now be described. In operation as a receiver the sheet I54 will be in the form of a suitable blank secured to a copyholder 28 by the necessary number of elastic bands I56 'or, if de sired and without departing from the spirit of the invention, by any sheet holder known to the prior'art. The stylus I1 if it is used in place of an exposure lamp or other recording device, will be in contact with the surface of the blank and the switches I10, I99 and 208 will be in their re- As scanning proceeds, the end of the received message is reached and the distant transmitter will function in the manner just described to connect the tone frequency generator to its outgoing line L. This constant frequency will be passed by the tuner 220 and upon detectionby the device 22I will energize the relay 224 causing it to deenergize the relay I13. The circuit of the operating coil I65 of the relay I66 is thus closed through back contact I12 of the relay I13. The relay I23 is deenergized when the armature of relay I13 leaves its front contact.

Preferably about one-third of a second delay occurs in the release of the relay I13 after opera-- tion of the relay 224. Deenergization of the relay I23 allows its contact tongue to interrupt the circuit of the phasing magnet 49, causing release allows'the synchronous motor to continue to run at synchronous speed.

The relay I66, energized as explained immediately above, causes the motor 93 to start, the split-nut to disengage under influence of the H magnet 2i, and the recording stylus I1 to be retracted from the copyholder or recording drum 29. The relay I90 does not function because it through the high resistance I61.

It is to be noted that the condenser circuit prevents any false operation of the drum changer due to momentary failures of the six thousand cycle tone during an idle period. This safeguard is obtained by taking advantage of the fact that the drum changer will not normally be operated twice in rapid succession. As long as the remote control signal from the transmitter is received, the split-nut is disengaged, the stylus is lifted from the paper and the phasing magnet 49 prevents rotation of the drum. It will be 'Seen that when the apparatus is operated as a receiver, the relay I66 which is unlocked locally has direct control over the drum changing motor 93 and joint control over the split nut release solenoid 2 I. If the remote control tone is still being received after the loading operation is completed, the magnet 2I is held operated through the circuit completed through the back contact of the relay 3 I23. The phasing magnet 49, also operated from relay I23 is under direct control of the relay I13 which in turn is directly controlled by the control signal received from the distant transmitter.

When the remote control tone is cut off by.

the distant transmitter, it being remembered that the moment of cut off coincides with an angular position of .the copyholder 28, the relay 224 releases its tongue which moves toward the left, energizing the relay I13, thus opening the operating circuit of the relay I66 and closing the circuit through the relay I23. The phasing magnet armature II 9 releases the driving spindle 43 at this instant. The receiving drums, to secure full advantage of the invention, are marked to facilitate putting the sheets I54 with the lap in a given place, and the stop arm H9 is so set that the received copy will.be in phase. This preliminary setting automatically takes care of the constantlag in the operation of the phasing apparatus and .results in all messages being received in their net 2I,.thus putting the machine in receiving condition.

' These occur only while the transmitting carrier is passing from light to dark portions of the copy, but at times they are sufficiently intense and frequent so that if any quick response detector control arrangement were used, it would result in false reception at the automatic equipment. It

will be seen, therefore, that the slow action feature introduced for example, by the relay I13 is an'important part of the system since it permits the employment of a control tone within thefrequency band-appearing in the output of the pickup device I6.

The copyhclders may also be changed at any time by closing the manual key 221 to initiate opcondenser 248 shunted by a resistance 248. The communication channel which connects the transmitterreceiver device with a distant transmitter or receiver is indicated by reference character L and the conductors I at the terminal stationconnected to the channel L are in communication with an optical pickup device I6 and may be placed in communication with the independent stylus I1' by means of a switch 252'depending on whether the apparatus is to be used as a transmitter or receiver. The anode of the rectifier 246 is connected to the secondary of a transformer 253 which is in turn connected to the condenser 248. The remaining condenser terminalis grounded as shown. The primary of the transformer 253 is connected across the conductors 25L The condenser 248 is shunted by a current limiting device such as a glow lamp 254, the purpose of which will be explained later.

The anode of the vacuum tube device 245 is connected to one point of a three point switch eration of the relay I66, to thereby start the with the magnet 2! of Figs. 2 and 3, and the magnets 58 and 23I may be operated by similar control circuits. The electro-optical pickup device I6 may be of any suitable kind and may be simi lar to that fully disclosed in the Wise patent previously referred to herein.

The optical pickup device I6, the stylus I1 and its associated apparatus, are supported by a movable carriage 233 which may be supported in precisely the same manner as described in connection with the carriage I9 of Fig. 1 of the drawings. The fixed base, a fragment of which is indicated at 234, is provided with a post 236 having a stop 231 which is engaged by a buffer 238, movable with the carriage 233. The buffer 238 is positioned to engage an arm 239 of a normally closed switch 240, to open the switch when the carriage is in its extreme left hand position.

The parts just described constitute a movable scanning system which is biased to the left as viewed on Fig. 5 by the flexible band 22, previously described, which is attached to any tensioning device, as for example the kind used to return the carriage of an ordinary typewriter. When a scanning operation is completed and magnets 59 and 23I are energized, the stylus I1 is withdrawn and the split nut 230 is raised from engagement with the screw 23, whereupon the carriage is drawn to the left by the cord 22 until buffer 238 opens the switch 240, and comes to 'rest against the post 231.

256. The movable contactof switch 256 is connected to the operating coil of a relay 251. The remaining terminal of this operating coil is connected to a suitable source of current. 258a. A second relay 258 is connected to ground by way of one contact tongue 26I and a make contact of the relay 251, through a condenser 262 shunted by a high resistance 263. Current for the operation of relay 259 is provided from the source 2581). A third relay 265 has its operating coil 266 connected to a stationary make contact which is engaged by a second contact tongue 261 of relay 251. The operating coil 2661s also supplied with energy from the source 258C.

The relay 265 is provided with a holding coil 210 which is adapted to be grounded at one terminal by the grounded relay contact tongue 2'. The remaining terminal of the holding coil 210 'is connected to the source 258d through the switch 239, which was illustrated and described in connection with Fig. 5 of the drawings. In addition toproviding the locking circuit for the relay 265, the contact tongue 21I thereof completes a circuit over the conductor 213 to one coil 215 of a relay 216, the circuit of the coil 215 including in series a lamp 211 and switch 30. The switch 30 is normally open, except when there are. no copyholders in the transmitterreceiver, and one terminal of switch 30 is grounded through the contact arm 4!. The relay 216 is provided with a second operating coil 2 8I which is connected in shunt with the cylinder changing motor 93. The motor 93 and the relay coil 28I are separately supplied from a suitable source 'of power 283 under control of the tongue 260 and the front contact of the relay 259. The switch I05 is operated by the cam I03 somewhat as described in connection with the switch I05 of Figs. 1 and, 3 of the drawings. However, the cam I03 holds the switch I05 open when the shaft 92 comes to rest. The tongue 2H and front contact of relay 265 are connected to the magnets 59 and 23I over the conductor 213 which is shown on Figs. 4 and 5 of the drawings. The conductor 285 of Figs. 3 and 5 is connected to the energy source 258e. Separate batteries 250a to 258e have been shown for simplicity of illustration but it is to be understood that a common battery may be employed.

In operation of the apparatus described and assuming that the transmitter-receiver is being operated as a transmitter, a message blank copyholder 28 provided with a message sheet I54 is assumed to be in operative position between the centers 32 and 42 of an apparatus like that disclosed in Figs. land 2 of the drawings. Since the apparatus depends upon an absence of a carrier signal from the pickup device 16, it is preferable to draw a line upon the sheet atone edge thereof and of a length equal to the length of the message.

By this means a signal will be sent at least once for each revolution of the copyholder 28 even though the scanning device 16 is traversing the portion of the sheet 154 between the-lines of the message. The pickup 16 transmits signals to the distant station over the communication channel L by way of conductors 261. The primary of the transformer 253 is also energized by these'signals.

I the signals appearing in the secondary of the l transformer 263 being rectified by the rectifier 246 246. The adjustable resistor 249 forms a very high resistance leak across the condenser 248.

The glow tube 245 sets an upper limit to the voltage charge that can be accumulated by the condenser 248. Since the condenser 248 is prefer- 9 6 has completed one revolution, the switch 105 is opened bythe cam 183, thus stopping the motor,

ably of small capacity, a few cycles of carrier current emitted by the pickup device 16 will charge the condenser 248 to the breakdown point of the glow lamp 254. This negative voltage is more than sufficient to reduce the plate current of the vacuum tube 245 to zero and therefore to keep the relay 251 deenergized as long as carrier current is received at relatively frequent inter I vals from the pickup device 16.

When line signals cease, the condenser 248 gradually discharges through the shunting resistance 249 and reduces the negative bias onthe grid of the tube 245. If signals from the pickup 16 remain oi: for a sufiicient period of time, the grid bias of the tube '245 will be reduced to such a point that plate current sufficient to operate the relay 251 will be produced. This timing can be regulated by the value of the resistance 249 which shunts the condenser 248. The neon lamp 264 has the advantage of making the delay period of the system substantially independent of the amplitude of signals emitted by the pickup device 16. It will be understood that a similar arrangement including a condenser 248 and a resistance 249 fed through a rectifier 246 by line signals is also used at the distant transmitterreceiver which, of course, operates as a receiver.

When the plate current in the tube 245 rises to a valuesufiicient to operate the relay 251 in the manner explained above, its right hand tongue 261 causes the relay 259 to be energized. This latter relay does not remain'operated, however, because of the large condenser 262 in series with its winding serving to limit its operating time to a relatively short period. Resistance 263 has a relatively high value and serves to discharge the condenser when the circuit is finally opened by.

the relay tongue 261. The contact of relay 259 remains closed for a suflicient time to start the motor 93 and advance the worm gear 94 and the the contacts of relay 259 having opened in the meantime. The mechanical parts function to replace the copyholder 28,with a fresh copyholder 265 locks up through contacts 239 .to insure that the magnets 231 and 59 will not be released until the carriage has completely returned, at which time the switch 239 is opened. 7

If no copyholders are available to be received .by the machine at the end of transmission or reception of a message, the switch 30 "is closed, which lights the signal lamp 211 and energizes the coil 215 of the relay 216 and also energizes the magnets 231 and 59 over conductor 213. .The relay 216 short circuits the line L over conductors 281. The relay 216 has its winding 281 connected across the terminals of the motor 93, as described, for the purpose of causing theline L to be short circuited over conductors 281 during operation of the automatic drum loading mechanism whereby no false signals can be transmitted to the line when the motor is operating. Such false signals if transmitted would be taken by the automatic machine at the receiving end as an indication of the beginning of anew message which would cause faulty operation.

The operation of. the arrangement of Fig. ,4 when the transmitter-receiver is being used as a receiver will be apparent, it is believed, from the foregoing description. However, a brief summary of its operation as a receiver will be given. It will be assumed that the independent stylus 11' is to be used for recording purposes and therefore the switch 252 will be closed. Incoming signals cam 183, (Fig. 1) to a point beyond which the switch 185 is closed. The motor 93 will draw current through the switch 165 after the contacts of relay 259 have opened and continue to run until the gear 95 has completed one revolution, as fully explained inconnection with the mechanical features disclosed by Figs. land 2. When the gear will energize the primary of the transformer 253 in precisely .the same manner as though these signalswere being produced by the local pickup device 16. These signals in turn will be rectified which controls the relay 251 to produce operation vof the drum changing mechanism.

The switch 256 may be connected to its upper point in circuit with the switch which is adapted to be engaged by the elastic copyholding bands. Therefore when the switch 256 is in its upper position, the system is the equivalent of that already described in connection with Fig. 3. A push button 288 is connected to relay winding 251 to cause manual energization of the relay 251 when desired so that a copyholder 28 may be ejected and replaced with a fresh copyholder at any time. Referring now in detail to Figs. 6 and 7,- which illustrate a modification of the mechanical parts of a copyholder changing apparatus embodying the present invention, numeral 290 indicates a supporting base provided with a rearwardly positioned raised portion 291,the latter serving to support a carriage 292 and the scanning motor also one or more guide surfaces 291 which engage respectively the groove 295 and the rail 294, to permit the carriage 292 to slide transversely as viewed on Fig. 6, but at the same time con- 12,988,888 straining it to move rectilinearly with respect to a copyholder in operative scanning position.

The carriage 292 carries an optical pick-up de- .ture member 302. The screw 30l is mounted for gated portion of the member 302 is slidable vertically in an aperture in the base of a magnet supporting frame 306. The top of the member 302 is formed as indicated at 301 so that it serves as an armature for the magnet 308, supported by the frame 306. A spring 309 holds the threaded recess firmly in engagement with the screw 30l so that as the screw is turned in the proper direction, the carriage will be propelled toward the right as viewed in Fig. 6. Upon disengagement of the member 302 from the screw when the magnet is energized, a cord 3 connected. to a suitable tensioning device'draws the carriage 292 toward the left, an operation which is accomplished automatically upon completion of a scanning operation. A pin 3I2 secured on the carriage 292 and accommodated'by a suitable slot in the raised portion of the base has a switch engaging member 3l3 thereof which is positioned to move the flexible switch arm 3l4 of a switch 3l5 of the normally closed type, when thecarriage 292 completes its travel to the left.

The scanning motor 293 imparts driving power to a copyholder spindle orshaft 3I1 which is equipped with a copyholder driving means 318. The copyholder driving means includes parts substantially identical with the parts 52, 53 and 54 illustrated on Fig. l of the drawings, therefore a detailed description of these parts will not The screw 30l is driven by gearing (not to a pin 326 which projects from the spindle 320, whereby the spindle 320 is biased toward the left as viewed in Fig. 6 of the drawings. To prevent rotation of the spindle 320, a key 321 engages the notch formed in the spindle receiving aperture in the upright 322.

" Copyholders 28, which initially are stored on a rack comprising rails 329 (Fig. 7) are fed into operative engagement with the centers 3l9 and 321 by modified apparatus embodying the invention, which will now be described. A pair of similar discs 331 and 332, notched about their peripheries as indicated at 333, are secured to a shaft 334, the latter being mounted for rotation in bearing brackets 331 and 338 secured to the base 290. In the embodiment shown each disc is provided with four notches 333 aligned with a like number. of notches in the cooperating disc. However, it will be understood that the discs 33I of the discs 33l and 332.

jecting from the spindle 320.

and 332 may, if desired, be provided with a greater or less number of notches and the operating mechanism for the discs modified accordingly.

The bracket 331 pivotally supports, on a horipivotally carried at its end upon an oscillatable' lever 348. The lever 341 is apertured at its end for engagement with a screw or other suitable fastening means at the end of the lever 348 (Fig. 6)., As the aperture which receives the screw 348 is slightly enlarged so that the pivotal connection between the two levers 341 and 348 is loose, a guiding notch is provided in the horizontal arm 350 of a bracket 35I secured to the upright member 331. Pins 353, corresponding in number to the number of notches 333 in each disc and equally spaced circumferentially of the disc 33l, areadapted to be engaged by a notch 354 formed at the upper end of the lever 341. The lever 341 is elongated'as indicated-at 353 so as to insure its engagement with one of the pins. A spring 351 anchored to the lever 341 and the bracket 35! biases the said lever inwardly so that its extension 356 presses against the pin 353 in position at any time in the cycle of rotation of the discs.

A crank member 359, pivotally carried at 360 upon a bracket 362, is bifurcated and notched at its upper end for engagement with pins 363 pro- As the lever 359 is rocked it will be seen that the spindle 320 will be reciprocated. The arm of the lever 359 which,

extends beyond the pivot point 360 is provided with a cam follower 361, the latter bearing against the periphery of a cam 368 carried by a cam shaft 310. It will be noted that the spring 325 extends to retain the follower 361 in engageand there is no cylinder in position to be grasped by the centers, the spindle 32 0 moves further to the left allowing the normally open switch 369 to operate the signal 311, as clearly shown in Fig. l

8. The bearing block 312 secured to the base 290 rotatably supports the shaft 310 at one end and the remaining end is rotatably carried by a bear. ing block 313 integral with or carriedby the forward wall of the portion 29l of the base.

A second cam 315 is keyed on the shaft 310 and the lobe thereof is so positioned that a normallyclosed switch 318 is opened by engagement of the said lobe with the resilient arm 319 of the switch on initial movement of the shaft 310 from its rest position. A third cam 381 of sector shape secured to the shaft 310 engages a cam follower roller 383 carried by the pivoted lever 348.

Driving power is imparted to the shaft 310 from a motor 384- through a worm gear 386 and a worm 381. The armature shaft 388 of the motor, to

which is secured the driving worm 381,a.lso carries a brake drum 389 which is frictionally engaged by 

